Bhagavad Gita Chapter 03, Text 05

Bg 3.5

na hi kascit ksanam api
jatu tisthaty akarma-krt
karyate hy avasah karma
sarvah prakrti-jair gunaih

Word for word: 
na — nor; hi — certainly; kascit — anyone; ksanam — a moment; api — also; jatu — at any time; tisthati — remains; akarma-krt — without doing something; karyate — is forced to do; hi — certainly; avasah — helplessly; karma — work; sarvah — all; prakrti-jaih — born of the modes of material nature; gunaih — by the qualities.

Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
Everyone is forced to act helplessly according to the qualities he has acquired from the modes of material nature; therefore no one can refrain from doing something, not even for a moment.

Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
It is not a question of embodied life, but it is the nature of the soul to be always active. Without the presence of the spirit soul, the material body cannot move. The body is only a dead vehicle to be worked by the spirit soul, which is always active and cannot stop even for a moment. As such, the spirit soul has to be engaged in the good work of Krishna consciousness, otherwise it will be engaged in occupations dictated by the illusory energy. In contact with material energy, the spirit soul acquires material modes, and to purify the soul from such affinities it is necessary to engage in the prescribed duties enjoined in the sastras. But if the soul is engaged in his natural function of Krishna consciousness, whatever he is able to do is good for him. The Srimad-Bhagavatam (1.5.17) affirms this:

tyaktva sva-dharmam caranambujam harer
bhajann apakvo ’tha patet tato yadi
yatra kva vabhadram abhud amusya kim
ko vartha apto ’bhajatam sva-dharmatah

“If someone takes to Krishna consciousness, even though he may not follow the prescribed duties in the sastras or execute the devotional service properly, and even though he may fall down from the standard, there is no loss or evil for him. But if he carries out all the injunctions for purification in the sastras, what does it avail him if he is not Krishna conscious?” So the purificatory process is necessary for reaching this point of Krishna consciousness. Therefore, sannyasa, or any purificatory process, is to help reach the ultimate goal of becoming Krishna conscious, without which everything is considered a failure.